For gasoline-powered hybrid vehicles and vehicles with stop-start systems, how shall the inspector complete the liquid fuel leak inspection?

• A. KOEO or "Ready"
• B. KOER
• C. Engine running
• D. After engine off

Answer: (A)

For gasoline-powered hybrids and stop-start systems, the liquid fuel leak inspection should be performed with the engine off but the fuel system pressurized, which is achieved by either KOEO (Key On, Engine Off) or placing the vehicle in its Ready state. In KOEO, you turn the ignition to the first position to power the electrical system and fuel pump without starting the engine, allowing leaks to be seen under normal fuel pressure. In hybrids, the engine may not run when the car is ready to drive, so the Ready state serves the same purpose: the vehicle is powered and the fuel system can be pressurized while the gasoline engine remains off. Testing under these conditions ensures leaks are detectable without the hazards and masking effects of a running engine. Checking while the engine is running would not be appropriate for this inspection, and a plain “engine off” without specifying KOEO/Ready may not guarantee the fuel system is properly pressurized for leak detection.